src/veritysetup.c

   1 /*
   2  * veritysetup - setup cryptographic volumes for dm-verity
   3  *
   4  * Copyright (C) 2012, Red Hat, Inc. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * version 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <stdarg.h>
  23 #include <errno.h>
  24 #include <string.h>
  25 #include <inttypes.h>
  26 #include <popt.h>
  27 #include <limits.h>
  28 #include <sys/stat.h>
  29
  30 #include "cryptsetup.h"
  31
  32 #define PACKAGE_VERITY "veritysetup"
  33
  34 static int use_superblock = 1;
  35
  36 static const char *hash_algorithm = NULL;
  37 static int hash_type = 1;
  38 static int data_block_size = DEFAULT_VERITY_DATA_BLOCK;
  39 static int hash_block_size = DEFAULT_VERITY_HASH_BLOCK;
  40 static uint64_t data_blocks = 0;
  41 static const char *salt_string = NULL;
  42 static uint64_t hash_start = 0;
  43 static const char *opt_uuid = NULL;
  44
  45 static int opt_verbose = 0;
  46 static int opt_debug = 0;
  47 static int opt_version_mode = 0;
  48
  49 static const char **action_argv;
  50 static int action_argc;
  51
  52 static int hex_to_bytes(const char *hex, char *result)
  53 {
  54         char buf[3] = "xx\0", *endp;
  55         int i, len;
  56
  57         len = strlen(hex) / 2;
  58         for (i = 0; i < len; i++) {
  59                 memcpy(buf, &hex[i * 2], 2);
  60                 result[i] = strtoul(buf, &endp, 16);
  61                 if (endp != &buf[2])
  62                         return -EINVAL;
  63         }
  64         return i;
  65 }
  66
  67 __attribute__((format(printf, 5, 6)))
  68 static void clogger(struct crypt_device *cd, int level, const char *file,
  69                    int line, const char *format, ...)
  70 {
  71         va_list argp;
  72         char *target = NULL;
  73
  74         va_start(argp, format);
  75
  76         if (vasprintf(&target, format, argp) > 0) {
  77                 if (level >= 0) {
  78                         crypt_log(cd, level, target);
  79 #ifdef CRYPT_DEBUG
  80                 } else if (opt_debug)
  81                         printf("# %s:%d %s\n", file ?: "?", line, target);
  82 #else
  83                 } else if (opt_debug)
  84                         printf("# %s\n", target);
  85 #endif
  86         }
  87
  88         va_end(argp);
  89         free(target);
  90 }
  91
  92 static void _log(int level, const char *msg, void *usrptr __attribute__((unused)))
  93 {
  94         switch(level) {
  95
  96         case CRYPT_LOG_NORMAL:
  97                 fputs(msg, stdout);
  98                 break;
  99         case CRYPT_LOG_VERBOSE:
 100                 if (opt_verbose)
 101                         fputs(msg, stdout);
 102                 break;
 103         case CRYPT_LOG_ERROR:
 104                 fputs(msg, stderr);
 105                 break;
 106         case CRYPT_LOG_DEBUG:
 107                 if (opt_debug)
 108                         printf("# %s\n", msg);
 109                 break;
 110         default:
 111                 fprintf(stderr, "Internal error on logging class for msg: %s", msg);
 112                 break;
 113         }
 114 }
 115
 116 static int _prepare_format(struct crypt_params_verity *params,
 117                            const char *data_device,
 118                            uint32_t flags)
 119 {
 120         static char salt_bytes[512];
 121
 122         params->hash_name = hash_algorithm ?: DEFAULT_VERITY_HASH;
 123         params->data_device = data_device;
 124
 125         if (salt_string && !strcmp(salt_string, "-")) {
 126                 params->salt_size = 0;
 127                 params->salt = NULL;
 128         } else if (salt_string) {
 129                 params->salt_size = strlen(salt_string) / 2;
 130                 if (hex_to_bytes(salt_string, salt_bytes) != params->salt_size)
 131                         return -EINVAL;
 132                 params->salt = salt_bytes;
 133         } else
 134                 params->salt_size = DEFAULT_VERITY_SALT_SIZE;
 135
 136         params->data_block_size = data_block_size;
 137         params->hash_block_size = hash_block_size;
 138         params->data_size = data_blocks;
 139         params->hash_area_offset = hash_start;
 140         params->hash_type = hash_type;
 141         params->flags = flags;
 142
 143         return 0;
 144 }
 145
 146 static int action_format(int arg)
 147 {
 148         struct crypt_device *cd = NULL;
 149         struct crypt_params_verity params = {};
 150         uint32_t flags = CRYPT_VERITY_CREATE_HASH;
 151         int r;
 152
 153         if ((r = crypt_init(&cd, action_argv[1])))
 154                 goto out;
 155
 156         if (!use_superblock)
 157                 flags |= CRYPT_VERITY_NO_HEADER;
 158
 159         r = _prepare_format(&params, action_argv[0], flags);
 160         if (r < 0)
 161                 goto out;
 162
 163         r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, opt_uuid, NULL, 0, &params);
 164         if (!r)
 165                 crypt_dump(cd);
 166 out:
 167         crypt_free(cd);
 168         return r;
 169 }
 170
 171 static int _activate(const char *dm_device,
 172                       const char *data_device,
 173                       const char *hash_device,
 174                       const char *root_hash,
 175                       uint32_t flags)
 176 {
 177         struct crypt_device *cd = NULL;
 178         struct crypt_params_verity params = {};
 179         uint32_t activate_flags = CRYPT_ACTIVATE_READONLY;
 180         char root_hash_bytes[128];
 181         int r;
 182
 183         if ((r = crypt_init(&cd, hash_device)))
 184                 goto out;
 185
 186         if (use_superblock) {
 187                 params.flags = flags;
 188                 params.hash_area_offset = hash_start;
 189                 r = crypt_load(cd, CRYPT_VERITY, &params);
 190         } else {
 191                 r = _prepare_format(&params, data_device, flags | CRYPT_VERITY_NO_HEADER);
 192                 if (r < 0)
 193                         goto out;
 194                 r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, NULL, NULL, 0, &params);
 195         }
 196         if (r < 0)
 197                 goto out;
 198         r = crypt_set_data_device(cd, data_device);
 199         if (r < 0)
 200                 goto out;
 201
 202         if (hex_to_bytes(root_hash, root_hash_bytes) !=
 203             crypt_get_volume_key_size(cd)) {
 204                 r = -EINVAL;
 205                 goto out;
 206         }
 207         r = crypt_activate_by_volume_key(cd, dm_device,
 208                                          root_hash_bytes,
 209                                          crypt_get_volume_key_size(cd),
 210                                          activate_flags);
 211 out:
 212         crypt_free(cd);
 213         return r;
 214 }
 215
 216 static int action_create(int arg)
 217 {
 218         return _activate(action_argv[0],
 219                          action_argv[1],
 220                          action_argv[2],
 221                          action_argv[3], 0);
 222 }
 223
 224 static int action_verify(int arg)
 225 {
 226         return _activate(NULL,
 227                          action_argv[0],
 228                          action_argv[1],
 229                          action_argv[2],
 230                          CRYPT_VERITY_CHECK_HASH);
 231 }
 232
 233 static int action_remove(int arg)
 234 {
 235         struct crypt_device *cd = NULL;
 236         int r;
 237
 238         r = crypt_init_by_name(&cd, action_argv[0]);
 239         if (r == 0)
 240                 r = crypt_deactivate(cd, action_argv[0]);
 241
 242         crypt_free(cd);
 243         return r;
 244 }
 245
 246 static int action_status(int arg)
 247 {
 248         crypt_status_info ci;
 249         struct crypt_active_device cad;
 250         struct crypt_params_verity vp = {};
 251         struct crypt_device *cd = NULL;
 252         struct stat st;
 253         char *backing_file;
 254         int i, path = 0, r = 0;
 255
 256         /* perhaps a path, not a dm device name */
 257         if (strchr(action_argv[0], '/') && !stat(action_argv[0], &st))
 258                 path = 1;
 259
 260         ci = crypt_status(NULL, action_argv[0]);
 261         switch (ci) {
 262         case CRYPT_INVALID:
 263                 r = -EINVAL;
 264                 break;
 265         case CRYPT_INACTIVE:
 266                 if (path)
 267                         log_std("%s is inactive.\n", action_argv[0]);
 268                 else
 269                         log_std("%s/%s is inactive.\n", crypt_get_dir(), action_argv[0]);
 270                 r = -ENODEV;
 271                 break;
 272         case CRYPT_ACTIVE:
 273         case CRYPT_BUSY:
 274                 if (path)
 275                         log_std("%s is active%s.\n", action_argv[0],
 276                                 ci == CRYPT_BUSY ? " and is in use" : "");
 277                 else
 278                         log_std("%s/%s is active%s.\n", crypt_get_dir(), action_argv[0],
 279                                 ci == CRYPT_BUSY ? " and is in use" : "");
 280
 281                 r = crypt_init_by_name_and_header(&cd, action_argv[0], NULL);
 282                 if (r < 0 || !crypt_get_type(cd))
 283                         goto out;
 284
 285                 log_std("  type:        %s\n", crypt_get_type(cd));
 286
 287                 r = crypt_get_active_device(cd, action_argv[0], &cad);
 288                 if (r < 0)
 289                         goto out;
 290
 291                 log_std("  status:      %s\n",
 292                         cad.flags & CRYPT_ACTIVATE_CORRUPTED ? "corrupted" : "verified");
 293
 294                 r = crypt_get_verity_info(cd, &vp);
 295                 if (r < 0)
 296                         goto out;
 297
 298                 log_std("  hash type:   %u\n", vp.hash_type);
 299                 log_std("  data block:  %u\n", vp.data_block_size);
 300                 log_std("  hash block:  %u\n", vp.hash_block_size);
 301                 log_std("  hash name:   %s\n", vp.hash_name);
 302                 log_std("  salt:        ");
 303                 if (vp.salt_size)
 304                         for(i = 0; i < vp.salt_size; i++)
 305                                 log_std("%02hhx", (const char)vp.salt[i]);
 306                 else
 307                         log_std("-");
 308                 log_std("\n");
 309
 310                 log_std("  data device: %s\n", vp.data_device);
 311                 if (crypt_loop_device(vp.data_device)) {
 312                         backing_file = crypt_loop_backing_file(vp.data_device);
 313                         log_std("  data loop:   %s\n", backing_file);
 314                         free(backing_file);
 315                 }
 316                 log_std("  size:        %" PRIu64 " sectors\n", cad.size);
 317                 log_std("  mode:        %s\n", cad.flags & CRYPT_ACTIVATE_READONLY ?
 318                                            "readonly" : "read/write");
 319
 320                 log_std("  hash device: %s\n", vp.hash_device);
 321                 if (crypt_loop_device(vp.hash_device)) {
 322                         backing_file = crypt_loop_backing_file(vp.hash_device);
 323                         log_std("  hash loop:   %s\n", backing_file);
 324                         free(backing_file);
 325                 }
 326                 log_std("  hash offset: %" PRIu64 " sectors\n",
 327                         vp.hash_area_offset * vp.hash_block_size / 512);
 328         }
 329 out:
 330         crypt_free(cd);
 331         if (r == -ENOTSUP)
 332                 r = 0;
 333         return r;
 334 }
 335
 336 static int action_dump(int arg)
 337 {
 338         struct crypt_device *cd = NULL;
 339         struct crypt_params_verity params = {};
 340         int r;
 341
 342         if ((r = crypt_init(&cd, action_argv[0])))
 343                 return r;
 344
 345         params.hash_area_offset = hash_start;
 346         r = crypt_load(cd, CRYPT_VERITY, &params);
 347         if (!r)
 348                 crypt_dump(cd);
 349         crypt_free(cd);
 350         return r;
 351 }
 352
 353 static __attribute__ ((noreturn)) void usage(poptContext popt_context,
 354                                              int exitcode, const char *error,
 355                                              const char *more)
 356 {
 357         poptPrintUsage(popt_context, stderr, 0);
 358         if (error)
 359                 log_err("%s: %s\n", more, error);
 360         poptFreeContext(popt_context);
 361         exit(exitcode);
 362 }
 363
 364 static void _dbg_version_and_cmd(int argc, const char **argv)
 365 {
 366         int i;
 367
 368         log_std("# %s %s processing \"", PACKAGE_VERITY, PACKAGE_VERSION);
 369         for (i = 0; i < argc; i++) {
 370                 if (i)
 371                         log_std(" ");
 372                 log_std("%s", argv[i]);
 373         }
 374         log_std("\"\n");
 375 }
 376
 377 static struct action_type {
 378         const char *type;
 379         int (*handler)(int);
 380         int required_action_argc;
 381         const char *arg_desc;
 382         const char *desc;
 383 } action_types[] = {
 384         { "format",     action_format, 2, N_("<data_device> <hash_device>"),N_("format device") },
 385         { "verify",     action_verify, 3, N_("<data_device> <hash_device> <root_hash>"),N_("verify device") },
 386         { "create",     action_create, 4, N_("<name> <data_device> <hash_device> <root_hash>"),N_("create active device") },
 387         { "remove",     action_remove, 1, N_("<name>"),N_("remove (deactivate) device") },
 388         { "status",     action_status, 1, N_("<name>"),N_("show active device status") },
 389         { "dump",       action_dump,   1, N_("<hash_device>"),N_("show on-disk information") },
 390         { NULL, NULL, 0, NULL, NULL }
 391 };
 392
 393 static void help(poptContext popt_context,
 394                  enum poptCallbackReason reason __attribute__((unused)),
 395                  struct poptOption *key,
 396                  const char *arg __attribute__((unused)),
 397                  void *data __attribute__((unused)))
 398 {
 399         struct action_type *action;
 400
 401         if (key->shortName == '?') {
 402                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 403                 poptPrintHelp(popt_context, stdout, 0);
 404                 log_std(_("\n"
 405                          "<action> is one of:\n"));
 406                 for(action = action_types; action->type; action++)
 407                         log_std("\t%s %s - %s\n", action->type, _(action->arg_desc), _(action->desc));
 408                 log_std(_("\n"
 409                          "<name> is the device to create under %s\n"
 410                          "<data_device> is the data device\n"
 411                          "<hash_device> is the device containing verification data\n"
 412                          "<root_hash> hash of the root node on <hash_device>\n"),
 413                         crypt_get_dir());
 414
 415                 log_std(_("\nDefault compiled-in dm-verity parameters:\n"
 416                          "\tHash: %s, Data block (bytes): %u, "
 417                          "Hash block (bytes): %u, Salt size: %u, Hash format: %u\n"),
 418                         DEFAULT_VERITY_HASH, DEFAULT_VERITY_DATA_BLOCK,
 419                         DEFAULT_VERITY_HASH_BLOCK, DEFAULT_VERITY_SALT_SIZE,
 420                         1);
 421                 exit(EXIT_SUCCESS);
 422         } else
 423                 usage(popt_context, EXIT_SUCCESS, NULL, NULL);
 424 }
 425
 426 static void show_status(int errcode)
 427 {
 428         char error[256], *error_;
 429
 430         if(!opt_verbose)
 431                 return;
 432
 433         if(!errcode) {
 434                 log_std(_("Command successful.\n"));
 435                 return;
 436         }
 437
 438         crypt_get_error(error, sizeof(error));
 439
 440         if (!error[0]) {
 441                 error_ = strerror_r(-errcode, error, sizeof(error));
 442                 if (error_ != error) {
 443                         strncpy(error, error_, sizeof(error));
 444                         error[sizeof(error) - 1] = '\0';
 445                 }
 446         }
 447
 448         log_err(_("Command failed with code %i"), -errcode);
 449         if (*error)
 450                 log_err(": %s\n", error);
 451         else
 452                 log_err(".\n");
 453 }
 454
 455 static int run_action(struct action_type *action)
 456 {
 457         int r;
 458
 459         log_dbg("Running command %s.", action->type);
 460
 461         r = action->handler(0);
 462
 463         show_status(r);
 464
 465         /* Translate exit code to simple codes */
 466         switch (r) {
 467         case 0:         r = EXIT_SUCCESS; break;
 468         case -EEXIST:
 469         case -EBUSY:    r = 5; break;
 470         case -ENOTBLK:
 471         case -ENODEV:   r = 4; break;
 472         case -ENOMEM:   r = 3; break;
 473         case -EPERM:    r = 2; break;
 474         case -EINVAL:
 475         case -ENOENT:
 476         case -ENOSYS:
 477         default:        r = EXIT_FAILURE;
 478         }
 479         return r;
 480 }
 481
 482 int main(int argc, const char **argv)
 483 {
 484         static char *popt_tmp;
 485         static struct poptOption popt_help_options[] = {
 486                 { NULL,    '\0', POPT_ARG_CALLBACK, help, 0, NULL,                         NULL },
 487                 { "help",  '?',  POPT_ARG_NONE,     NULL, 0, N_("Show this help message"), NULL },
 488                 { "usage", '\0', POPT_ARG_NONE,     NULL, 0, N_("Display brief usage"),    NULL },
 489                 POPT_TABLEEND
 490         };
 491         static struct poptOption popt_options[] = {
 492                 { NULL,              '\0', POPT_ARG_INCLUDE_TABLE, popt_help_options, 0, N_("Help options:"), NULL },
 493                 { "version",         '\0', POPT_ARG_NONE, &opt_version_mode, 0, N_("Print package version"), NULL },
 494                 { "verbose",         'v',  POPT_ARG_NONE, &opt_verbose,      0, N_("Shows more detailed error messages"), NULL },
 495                 { "debug",           '\0', POPT_ARG_NONE, &opt_debug,        0, N_("Show debug messages"), NULL },
 496                 { "no-superblock",   0,    POPT_ARG_VAL,  &use_superblock,   0, N_("Do not use verity superblock"), NULL },
 497                 { "format",          0,    POPT_ARG_INT,  &hash_type,        0, N_("Format type (1 - normal, 0 - original Chrome OS)"), N_("number") },
 498                 { "data-block-size", 0,    POPT_ARG_INT,  &data_block_size,  0, N_("Block size on the data device"), N_("bytes") },
 499                 { "hash-block-size", 0,    POPT_ARG_INT,  &hash_block_size,  0, N_("Block size on the hash device"), N_("bytes") },
 500                 { "data-blocks",     0,    POPT_ARG_STRING, &popt_tmp,       1, N_("The number of blocks in the data file"), N_("blocks") },
 501                 { "hash-start",      0,    POPT_ARG_STRING, &popt_tmp,       2, N_("Starting block on the hash device"), N_("512-byte sectors") },
 502                 { "hash",            'h',  POPT_ARG_STRING, &hash_algorithm, 0, N_("Hash algorithm"), N_("string") },
 503                 { "salt",            's',  POPT_ARG_STRING, &salt_string,    0, N_("Salt"), N_("hex string") },
 504                 { "uuid",            '\0', POPT_ARG_STRING, &opt_uuid,       0, N_("UUID for device to use."), NULL },
 505                 POPT_TABLEEND
 506         };
 507
 508         poptContext popt_context;
 509         struct action_type *action;
 510         const char *aname, *null_action_argv[] = {NULL};
 511         int r;
 512
 513         crypt_set_log_callback(NULL, _log, NULL);
 514
 515         setlocale(LC_ALL, "");
 516         bindtextdomain(PACKAGE, LOCALEDIR);
 517         textdomain(PACKAGE);
 518
 519         popt_context = poptGetContext("verity", argc, argv, popt_options, 0);
 520         poptSetOtherOptionHelp(popt_context,
 521                                N_("[OPTION...] <action> <action-specific>"));
 522
 523         while((r = poptGetNextOpt(popt_context)) > 0) {
 524                 unsigned long long ull_value;
 525                 char *endp;
 526
 527                 errno = 0;
 528                 ull_value = strtoull(popt_tmp, &endp, 0);
 529                 if (*endp || !*popt_tmp ||
 530                     (errno == ERANGE && ull_value == ULLONG_MAX) ||
 531                     (errno != 0 && ull_value == 0))
 532                         r = POPT_ERROR_BADNUMBER;
 533
 534                 switch(r) {
 535                         case 1:
 536                                 data_blocks = ull_value;
 537                                 break;
 538                         case 2:
 539                                 hash_start = ull_value * 512;
 540                                 break;
 541                 }
 542
 543                 if (r < 0)
 544                         break;
 545         }
 546
 547         if (r < -1)
 548                 usage(popt_context, EXIT_FAILURE, poptStrerror(r),
 549                       poptBadOption(popt_context, POPT_BADOPTION_NOALIAS));
 550
 551         if (opt_version_mode) {
 552                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 553                 poptFreeContext(popt_context);
 554                 exit(EXIT_SUCCESS);
 555         }
 556
 557         if (!(aname = poptGetArg(popt_context)))
 558                 usage(popt_context, EXIT_FAILURE, _("Argument <action> missing."),
 559                       poptGetInvocationName(popt_context));
 560         for(action = action_types; action->type; action++)
 561                 if (strcmp(action->type, aname) == 0)
 562                         break;
 563         if (!action->type)
 564                 usage(popt_context, EXIT_FAILURE, _("Unknown action."),
 565                       poptGetInvocationName(popt_context));
 566
 567         action_argc = 0;
 568         action_argv = poptGetArgs(popt_context);
 569         /* Make return values of poptGetArgs more consistent in case of remaining argc = 0 */
 570         if(!action_argv)
 571                 action_argv = null_action_argv;
 572
 573         /* Count args, somewhat unnice, change? */
 574         while(action_argv[action_argc] != NULL)
 575                 action_argc++;
 576
 577         if(action_argc < action->required_action_argc) {
 578                 char buf[128];
 579                 snprintf(buf, 128,_("%s: requires %s as arguments"), action->type, action->arg_desc);
 580                 usage(popt_context, EXIT_FAILURE, buf,
 581                       poptGetInvocationName(popt_context));
 582         }
 583
 584         if (opt_debug) {
 585                 opt_verbose = 1;
 586                 crypt_set_debug_level(-1);
 587                 _dbg_version_and_cmd(argc, argv);
 588         }
 589
 590         r = run_action(action);
 591         poptFreeContext(popt_context);
 592         return r;
 593 }